Anti-Spoofing Method Using Double Peak Detection in the Two-Dimensional C/A Code Search Space
권금철 Keum Cheol Kwon , 양철관 Cheol Kwan Yang , 심덕선 Duk Sun Shim
17(2) 157-164, 2013
권금철 Keum Cheol Kwon , 양철관 Cheol Kwan Yang , 심덕선 Duk Sun Shim
DOI: JANT Vol.17(No.2) 157-164, 2013
In the presence of spoofing signal the GPS signal having the same PRN with the spoofer is hard to be acquired since the power of spoofing signal is usually stronger than that of GPS signal. If a spoofing signal exists for the same PRN, there are double peaks in two-dimensional space of frequency and code phase in acquisition stage. Using double peak information it is possible to detect spoofing signal and acquire GPS information through separate channel tracking. In this paper we introduce an anti-spoofing method using double peak detection, and thus can acquire GPS navigation data after two-channel tracking for the same PRN as the spoofing signal.
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The Design and Implementation of Driver Safety Assist System by Analysis of Driving Behavior Data
고재진 Jae Jin Ko , 최기호 Ki Ho Choi
17(2) 165-170, 2013
고재진 Jae Jin Ko , 최기호 Ki Ho Choi
DOI: JANT Vol.17(No.2) 165-170, 2013
In this paper, we propose the information acquisition and analysis system for a vehicle driver in order to provide the safe driving environments. We first define the list of reckless driving behaviors and propose the recognition system, which recognizes the reckless behaviors, by using the acquired information. The collaboration among the information acquisition, the analysis, and the behavior comparison modules increases the accuracy of the recognition rate. Our system alarms to a vehicle driver in order to notify the potential to confront the dangerous situation due to the abnormal or reckless driving behaviors.
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Miniaturized folded-slot antenna for 2.4 GHz ZigBee module
이영순 Young Soon Lee , 유진하 Jin Ha Yoo
17(2) 171-176, 2013
이영순 Young Soon Lee , 유진하 Jin Ha Yoo
DOI: JANT Vol.17(No.2) 171-176, 2013
A microstrip-fed miniaturized folded-slot antenna that is cut at the finite ground plane edge for the size reduction is proposed as a ZigBee module operating in the 2.4GHz frequency band, as specified by the IEEE standard 802.15.4. The antenna is fabricated within space limited to 35 mm × 9 mm on a 35mm × 35mm substrate, which is about the PCB size of a typical wireless ZigBee module. The measured impedance bandwidth and antenna gain are 2.37∼2.49GHz and 2.4dBi respectively. The measured radiation patterns are similar to conventional folded-slot antennas and are also stable across the pass band. These properties and its compact structure help in making the antenna suitable for ZigBee module.
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Design of patch antenna combined with slots for smart GPS module
장민규 Min Gyu Jang , 이영순 Young Soon Lee , 조동균 Dong Kyun Cho
17(2) 177-182, 2013
장민규 Min Gyu Jang , 이영순 Young Soon Lee , 조동균 Dong Kyun Cho
DOI: JANT Vol.17(No.2) 177-182, 2013
In this paper, printed antenna which can be applied to a built-in wireless module of the security controller operating at global positioning system(GPS) L1 frequency band(1.575GHz) is proposed. The proposed antenna is basically composed of a microstrip patch antenna with inserting feed. In particular left and right slots which are respectively asymmetric are used for impedance matching, whereas slot with one open-end and shorting point are used on the bottom plane to set operating frequency and enhance bandwidth. It is observed at the desired GPS L1 frequency band that the radiation efficiency and gain of the proposed antenna are 90% and more than 4.8dBi respectively.
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Solution of TE Scattering by a Conductive Strip Grating Over the Grounded Two Dielectric Layers with Edge Boundary Condition
윤의중 Uei Joong Yoon
17(2) 183-188, 2013
윤의중 Uei Joong Yoon
DOI: JANT Vol.17(No.2) 183-188, 2013
In this paper, the TE (Transverse Electric) scattering problems by a perfectly conducting strip grating over a grounded two dielectric layers with edge boundary condition are analyzed by applying the FGMM (Fourier Galerkin Moment Method). For the TE scattering problem, the induced surface current density is expected to the zero value at both edges of the strip, then the induced surface current density on the strip is expanded in a series of the multiplication of the Chebyshev polynomials of the second kind and the functions of appropriate edge boundary condition. The numerical results shown the fast convergent solution and good agreement compared to those of the existing papers.
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A History-based Dynamic Thread Pool Method for Reducing Thread Creation and Removal Overheads
오삼권 Sam Kweon Oh , 김진섭 Jin Sub Kim
17(2) 189-195, 2013
오삼권 Sam Kweon Oh , 김진섭 Jin Sub Kim
DOI: JANT Vol.17(No.2) 189-195, 2013
In an environment with frequent job requests and short job processing times, thread pool methods are frequently used to increase throughput by reducing overheads due to thread creation and removal. A watermark method normally reduces unnecessary uses of resources by keeping the number of threads less than those needed in the maximum. In the absence of available threads, however, it processes jobs by creating additional threads up to a specified limit so that the system overhead increases due to creation of threads, which results in throughput degradation. This paper presents a history-based dynamic method that alleviates throughput degradation. By estimating and maintaining the number of threads needed for jobs, it reduces overheads due to thread creation and removal. According to experiments, compared to the watermark thread pool method, it shows average 33% increase in the number of threads kept and average 62% reduction in the number of threads created, which results in 6% increase in terms of system throughput.
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Dual-Mode Balanced Filter in Symmetric Composite Right/Left-Handed Transmission Line Structure
김영 Young Kim , 심석현 Seok Hyun Sim , 윤영철 Young Chul Yoon
17(2) 196-201, 2013
김영 Young Kim , 심석현 Seok Hyun Sim , 윤영철 Young Chul Yoon
DOI: JANT Vol.17(No.2) 196-201, 2013
In this paper, a dual-mode balanced filter with symmetric coupled composite right/left-handed transmission line is introduced. Unlike the other symmetric structure, this configuration has the ability to operate under both common- and differential-mode excitation. These properties are achievable through providing physical short circuit by means of ground vias at the center of each unit-cell along the symmetry plane of the structure. Because the CRLH unit-cells are operated under both common- and differential-mode excitation, we implemented a balanced filter using these properties. To validity these features, a five-cell four port coupled CRLH-TL is simulated, fabricated and measured and the obtained performances agree with the simulation results under both common- and differential-mode excitation.
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Unequal Power Divider using Parallel Connection Transmission Line
권상근 Sang Keun Kwon , 김영 Young Kim , 윤영철 Young Chul Yoon
17(2) 202-207, 2013
권상근 Sang Keun Kwon , 김영 Young Kim , 윤영철 Young Chul Yoon
DOI: JANT Vol.17(No.2) 202-207, 2013
In this paper, a high dividing ratio unequal power divider using parallel connection transmission line is presented. Because a very low impedance transmission line can`t implement a microstrip technology, this can fabricate a parallel connection transmission line with high impedance. When we design a high dividing ratio divider, we need the very low impedance line. The parallel connection transmission line could be implemented to obtain a low impedance line characteristic. To validity this approach, we are implemented a 10:1 unequal divider at center frequency 1 GHz. The performances of power divider agree with simulation results.
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Compensation Characteristics of WDM Signals Depending on RDPS Slope of Fiber Span in Dispersion Managed Optical Transmission Links
이성렬 Seong Real Lee
17(2) 208-217, 2013
이성렬 Seong Real Lee
DOI: JANT Vol.17(No.2) 208-217, 2013
The optimal residual dispersion per span (RDPS) slope is induced through the analyses of the compensation characteristics of the wavelength division multiplexed (WDM) channels depending on RDPS slope in the optical links with a dispersion management (DM) and an optical phase conjugation. The simulation results show that the effective launch power of WDM is more increased and the performance difference between the channels is more decreased as RDPS slope is more increased. The simulation results also show that the effective net residual dispersion (NRD) range is more increased as RDPS slope is more increased, and consequently, it is more advantageous to use the large RDPS slope for implementing the flexible optical links.
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Traffic Congestion Control Using PQS in Wireless Multimedia Sensor Networks
이종득 Chong Deuk Lee
17(2) 218-224, 2013
이종득 Chong Deuk Lee
DOI: JANT Vol.17(No.2) 218-224, 2013
Uplink overflow in WMSN (Wireless Multimedia Sensor Networks) aggravates the resource consumption, delay, and traffic congestion. This paper proposes a new traffic congestion control mechanism using popularity. The proposed mechanism controls congestions by dispersing the media traffic, and it control fairly packets according to priority. This paper proposes PQS (Packet Queue Scheduler) to control fairly packets, and the proposed mechanism provides a fair opportunity to all sensor nodes without a specific location. The simulation results show that the proposed mechanism achieves improved performance in throughput, delay ratio, link quality, and buffer queue control ratio compared with those of other existing methods.
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Basic Prototype Design and Verification of Hadoop Cluster based on Private Cloud Infrastructure for SMB
차병래 Byung Rae Cha , 김형균 Hyeong Gyun Kim , 김대규 Dae Gue Kim , 김종원 Jong Won Kim , 김용일 Yong Il Kim
17(2) 225-233, 2013
차병래 Byung Rae Cha , 김형균 Hyeong Gyun Kim , 김대규 Dae Gue Kim , 김종원 Jong Won Kim , 김용일 Yong Il Kim
DOI: JANT Vol.17(No.2) 225-233, 2013
Recently, Cloud Computing and Big Data has become a buzzword in the field of IT. In this paper, as part of special efforts to support small businesses (SMB) in these situations, we designed the basic prototypes ver. 0.1, 0.2, and 0.5 for Hadoop cluster based on private cloud infrastructure and implemented the part of basic prototypes. And we verified the performances of the basic prototypes using ASA Dataset.
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Development of tangible language content system based on voice recording
나종원 Jong Won Na
17(2) 234-239, 2013
나종원 Jong Won Na
DOI: JANT Vol.17(No.2) 234-239, 2013
Learning a lesson about poor concentration and problems of the existing content, the system of language which could not be determined, Many teachers` assessment decision was made. As a result, voice recording based on the combination of ubiquitous technology and virtual reality technology, and install the projector in a classroom Through the learning content corresponding grade English student ID card attached RFID reader in each classroom, and students of RFID tags attached. In reality of the virtual three-dimensional image content foreigners and question-and-answer using the voice recording technology at the same time check the pronunciation and intonation level passes or level failure judged. Student education data to a central server system is configured to do so after saving to the DB through a feedback process, which provides information. Analysis of the issues that can have a common language content in the present study and Problem for voice recording technology to solve the problem and did not solve the existing language in the content level based classes.
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Airtouch technology smart fusion DID system design
이광용 Gwang Yong Lee , 황부현 Bu Hyun Hwang
17(2) 240-246, 2013
이광용 Gwang Yong Lee , 황부현 Bu Hyun Hwang
DOI: JANT Vol.17(No.2) 240-246, 2013
Airtouch technology to integrate the system in the way of information delivery devices, touch screen DID this study is to develop new ways of information delivery systems. Airtouch technology to design and implement a system that can be utilized to view the college campus announcements, education, information, and employment information, and store the remote operation and sharing content, the development of cloud services to sync content via smart technology implementation fusion DID systemto develop. Packs USB interface kinek because you may be used in connection with the information appliances, and low-cost product by leveraging the Kinect sensor, Airtouch technology implementation. Types of input devices paper Airtouch technology systems, the user`s hand gestures alone can interact with information appliances, smart fusion system developed by DID by tracking the user`s hand movements to manipulate the mouse pointer, and information through the user`s hand gestures to command the unit so that you can make. Airtouch technology smart fusion DID system technology utilizing a ripple effect on other industries, such as the online education industry, advertising, information industry increases. Also, replace the existing interface device with the versatility of a wide range of technologies, usability is an infinite expansion.
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AdaBoost-Based Gesture Recognition Using Time Interval Trajectory Features
황승준 Seung Jun Hwang , 안광표 Gwang Pyo Ahn , 박승제 Seung Je Park , 백중환 Joong Hwan Baek
17(2) 247-249, 2013
황승준 Seung Jun Hwang , 안광표 Gwang Pyo Ahn , 박승제 Seung Je Park , 백중환 Joong Hwan Baek
DOI: JANT Vol.17(No.2) 247-249, 2013
The task of 3D gesture recognition for controlling equipments is highly challenging due to the propagation of 3D smart TV recently. In this paper, the AdaBoost algorithm is applied to 3D gesture recognition by using Kinect sensor. By tracking time interval trajectory of hand, wrist and arm by Kinect, AdaBoost algorithm is used to train and classify 3D gesture. Experimental results demonstrate that the proposed method can successfully extract trained gestures from continuous hand, wrist and arm motion in real time.
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